Control valve



Jan. 3, 1956 R. G. OLSON 2,72

CONTROL VALVE Filed April 14, 1953 2 Sheets-Sheet 2 i6 25 116 R 210 g1.18

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United States Patent 2,729,242 CONTROL vALvE' Raymond G. 0ls0n,-Niles,Illa assignor of one-half to Kennetll T. Snow, Oak Park, Ill.

Application- April 14, 1953',-Seria lNo. 3485775 6 Claims. or. 137-4922This invention relates to anew and improved control valve.

The control offluid operated equipment has long been a major problem forindustry. The operation of machines or parts thereof by fluid underpressure whether it be gas or liquid is becoming more and moreprevalent; Usually cylinders with pistons therefor are employed todirectly perform some mechanical function. Thus the positive control ofpiston extension or retraction is extremely important to commercialsuccess.

it is therefore a principal object of this invention to provide acontrol valve for fluid operated equipment.

An important object of this invention is the provision of a controlvalve for fluid operated equipment wherein in response to incoming fiuidunder pressure the control valve is assisted in its shifting movement.

Another and further important object of this invention is the provisionof a control valve wherein fluid under pressure may be alternately movedin either of two directions.

Another and still further important object of this invention is tosupply a control valve for fluid operated equipment which can create astatus quo of all fluid under pressure in the system at any time or maydirect fluid in either of two directions;

Still another important object of this invention is to provide a controlvalve for fluid operated equipment wherein the valve will automaticallycenter after each operation thereof.

A still further modified form of control valve may be actuated tooperate one way or the opposite way to direct fluid under pressure ineither direction and the control valve will move through thefulldistance thereof and remain in its end position.

A further object er this invention seriatire arteries of a control valveby the manual bleeding or discharging of'all fluid from one end or theother where'aftr incorrimg fluid under pressure will cause a shifting ofthe control vaIve.

Another iniportantobject of this invention residesv in the means forentrappirrg fluid bled from a control val e;

Other" and further important objects and advantages" will becomeapparent from the disclosures in the following specification andaccompanying drawings.

In the" drawings:

Figure 1 is a longitudinal sectional view of the control valve of thisinvention and includirig various associated elements in dia rammaticillustration,

Figure 2 is a view similar to Figure 1 wherein the valve is shown inshifted position for effecting a directing of fluid under pressureto'one end of the fluidcylinder to be operated.

Figure 3' is a longitudinal sectional view of a modified form of valveincorporating all of the principles of the valve of Figures 1 and 2except ref the self centering thereof.

Figure 4 is a still further stashed reins of emitter" valve using afluid entrappirig' means atthe pointsof.

bleeding at both ends of the control valve.-

Asshown in'the drawings: The reference-numeral 10 indicates generally ahousing or" body for the control valve of this invention.

posed bore or passage 11. The ends of the' passage II are threadedinternally as shownat 12- and 13; plugs 14 and 15 having reduceddiameter shoulders. 16 and 17 which are externally threaded at 18' and19 en gage the internally threaded passage ends 12 and 1-3 of thehousing.

The housing l'il'has an inlet port or passage 20 to receive fluid underpressure. The function of the control valve of this invention is toreceive fluid under pressure and The spool valve is provided withlongitudinally spaced" apart annular grooves or recesses 26, 27, and 23.End lands 29 and St) on the slide valve 25 lie adjacent the outergrooves 26 and 28'. Spaced apart intermediate annula'r lands 31 and 32flank the central annular groove 27 and lie within the grooves 26 and28. The spool is further identified with a longitudinally extendingpassage 33 disposed substantially centrally thereof. Radial passages 34and 35 in the valve 25 join the centrally disposed annular groove 27with the longitudinally extending passage 33 within the valve.

Internally of the spool valve there is provided external- 1y threadedsleeves or bushings 36 and 37 which threadedly engage spaced apartinternally threaded portions 38 and 39 of the passage 33'; The bushings36 and 37 are themselves provided with longitudinally extending"generally centrally located, aligned passages 40 and 41- of equaldiameter through which fluid is permitted to pass from the center of thespool valve adjacent the radial passages to the ends of the spool valve25. Each bushing 36 and 37 is equipped with a screwdriver slot- 42" and43' respectively in the outer ends thereof for the purpose of assemblyor removal within the spool 25. The inner ends 44 and 45 of the bushings36 and 37 coristitute spaced apart valve seats and further define achamber 4 6 therebetwee'n. A small center valve member 47' is positionedwithin the chamber 46 and is adaptec'i toengag'e either of the valveseats 44 or 45'to thus sub"- stantial'ly close off or restrict passageof fluid to either end of the spool valve. The valve 47 is provided withalongitudinally extending small diainetered bleed hole 48' therethrough.Th'e bleed hole 4-8 is substantially e611 tral'ly disposed and serves toprevent the complete lo'se on of fluid to one side or the other. it isthe effective diife'ren'tial in the diameters of the passages- 40 and4'1 with respect to the valve passage 48 that makes this deviceelrectivel-y operate as will later be described;

The passage 33- through the spool valve has enlarged end openings 49 and59 disposed outwardly of the thread= ed'bushings 36 and 37. Theseopenings or chambers 49 and 5t) are adapted to receive the inner ends ofhelically Wound coil springs 51 and 52. The springs 51v and 52extendoutwardly in oppositedirectionsand abut against washers 53' and 54respectively. The washers lie against the inner ends of the threadedshoulders 16 and 17 and itvmr h s e seen that the spr ngs 51 aid 52 areconfirid within the valve hoiising The springs are of equal PatentedJan. 3, 1956' The: housing 10 is preferably a casting'and isequippedwitha longitudinally extending and generally centrally dis strength inorder to cause a normal automatic centering of the spool valve withinthe longitudinal bore of the housing 10.

The end plugs 14 and 15 are equipped with hollowed chambers 55 and 56within the shoulders 16 and 17. Retaining washers 57 and 58 arepositioned at the inner ends of the chambers 55 and 56 and are securelyheld by inturned lips 59 and 60 formed from the shoulder peripheries.Springs 61 and 62 are disposed within the chambers 55 and 56 and attheir one ends abut the fixed washers 57 and 58. End fluid bleedingvalves 63 and 64 are positioned within the chambers 55 and 56respectively and are arranged and constructed to close centrally locatedopennigs 65 and 66 in the end plugs 14 and 15. Post members or valvestems are integrally mounted on the end valves and project through theopenings 65 and 66 respectively. The springs 61 and 62 normally urge thevalves 63 and 64 to closed positions with the end plugs 14 and 15 andthus maintain the holes 65 and 66 closed to the passage of fluid. Amanual depression of either valve operating stem 67 or 63 causes therespective valve to move inwardly against the action of the holingspring 61 or 62 and at that time permit the passage of fluid from withinthe valve housing 1 The control valve of this invention is used aspreviously stated with hydraulic or fluid equipment and thus in order toshow the environment thereof the other necessary elements have beenshown in a rather diagrammatic fashion to complete a fluid circuit orsystem. A compressor or fluid pump is shown diagrammatically at 69. Thiscompressor is arranged and constructed to deliver fluid under pressureto the control valve whereafter it is directed in the manner asdetermined by the control valve. A fluid operated cylinder 78 having apiston 71 slidable therein is representative of the device which is tobe operated by the control valve. The reference numeral 72 is adiagrammatic illustration of a conduit joining the compressor to theinlet port 2% of the valve. Similarly the reference numeral 73represents the joining of the valve outlet port 21 to one end of thefluid cylinder 70. The other conduit is shown at 74 and joins the spacedapart outlet port 22 to the other end of the fluid cylinder 70. Thusfluid under pressure may be delivered to either end of the cylinder 79to effect a movement of the piston 71 in either direction depending uponthe position of the spool within the control valve housing. An exhaustconduit is illustrated at 75 for joining the exhaust port 23 to a fluidreservoir (not shown). The other exhaust port 24 is joined by a conduit76 also leading to the same fluid reservoir whereby the fluid circuit iscompleted. The reservoir, of course, delivers fluid to the compressorfor recirculation as called for by the apparatus.

In the operation of the device the compressor or pump 69 continuallydelivers fluid under pressure to the control valve whereupon it passesthrough the inlet port around the annular groove 27 and thence passingoutwardly through restricted passages to the outlet ports 21 and 22inasmuch as both ports are slightly cracked to the groove 27. In thisposition as shown in Figure 1 the spool valve is centered within thehousing 10 and it should be understood when the valve is so centered theposition of the piston 71 in the cylinder to be controlled remainsstationary. The balanced springs and the balanced fluid pressure in eachend of the valve insures this static central position. In order toeffect movement of the spool valve and a change in the direction of flowof fluid one end valve 63 or 64 is necessarily opened to permit escapeof fluid within the central passage of the spool 25. As shown in Figurel the stem 68 is depressed as indicated by the arrow 77 whereupon thevalve 64 leaves its seat around the opening 66 in the end plug enablingfluid to pass outwardly therefrom. The inside of the spool valve isusually filled with fluid by reason of the entry of the fluid from theinlet through the radial 47 is occasioned by two happenings.

4 passages 34 and 35 into the chamber 46 between the bushings 36 and 37.

The opening of the end valve 64 permits the escape of the internal fluidat that end of the control valve with the result that the central valve47 is drawn or sucked into engagement with the valve seat 45 on thebushing 37 adjacent the end of the control valve having the end valveopened. The movement of the small internal valve One of course, is theexhaustion of fluid from the seat and a natural tendency of the valve tomove along with the fluid to a seated position. The second occurs by thebuilding up of fluid pressures in the opposite end of the spool valve toan extent where the unbalancing of fluid pressures causes the valve 47to be forced to a seated position. Simultaneously with the substantialclosing of the fluid passage Within the spool valve the whole spool isforced to move longitudinally Within the housing toward the opened endvalve. The spool valve movement is occasioned by substantially all ofthe same reasons as the closing of the small central valve 47 butprincipally by reason of the unbalanced condition of fluid within thehousing which overcomes the forces of the balanced springs 51 and 52. Itis material to the successful operation of this device that the centralpassage within the spool valve be not completely closed. The shifting ofthe valve 47 to either one side or the other causes a differential inthe size of the central passage iii-41 to either one end or the otherwhereupon the spool or slide valve will have rapid movement to one endor the other of the housing. Immediately after shifting of the spoolvalve in one direction incoming fluid under pressure in the pathindicated by the arrow 79 is barred from entering one of the outletports 21 or 22 and is permitted greater and greater entry into the otherone of them. Continuing with the example wherein the end valve 64 hasbeen opened, the spool valve moves toward that valve causing a closingof the outlet port 21 and a full opening of the port 22. This directsdelivery of fluid under pressure in the direction of the arrow 84)through the conduit 74 to one end of the fluid operated cylinder '70wherein the piston 71 is caused to recede within the cylinder. Of coursethe fluid in the cylinder 70 behind the piston must be discharged andthis is accomplished through the conduit 73 in the direction of thearrow 81 to the outlet port 21 and thence around the annular groove 26to the exhaust port 23. This port 23 as previously stated returns thefluid through the conduit 75 in the direction or" the arrow 82 to areservoir where it may be used for recirculation. The control valve thusperformed the function of controlling movement of the fluid equipment.However, the operation of the control valve is not completed. If the endvalve 64 is released from its state of manual depression the spool valvewill immediately seek a balance within the housing. This balance seekingoccurs by the fluid under pressure bleeding through the hole 48 in thecentral valve 47 to the chamber within the spool valve just recentlyexhausted of its fluid. Soon this fluid builds up sufficiently so thatadded to the effective strength of the compressed spring 52 the spoolvalve tends to center within the housing. Similarly when the fluidwithin the one end of the valve balances the fluid within the other endthe valve 47 relaxes its seating position and tends to float centrallywithin the chamber 46 between the spaced apart valve seats 44 and 45.Although the workings of this control valve have taken considerable timeand words to explain, in actual operation they function quite rapidly.The opening of an end valve results in instantaneous movement of thepiston 71 in the fluid operated cylinder 70. And, similarly the closingof the end valve halts further movement of the piston 71.

The operation of the device resulting from the depression of the endvalve 64 has been rhetorically described and is shown pictorially inFigures 1 and 2 of the drawings. Let us now assume that the end valve 63is deseat 44 and the spoolvalve moves" longitudinally within the bore 9t q sins a a s th i sti of h spring Hfiidlkfie i t i' fi q i herumpj 6now directed to the end" of the cylinder 70 wherein the piston is forcedinto extended position; The fluid within the cylinder 70' on the9llfir$id of the piston 71 is exhausted throu h the control vaive to thereservoir.

Thus 1 1 sv defitthat the sit b a e a e e movement of fluid operatedequipment in either direction;

The device of Figure- 3' is a slight modification from the valve asshown'in Figures land 2: The only material Change s h i i t'en' th sat s5. mi which makes the controlvalve non centering and non -stoppableintermediate the ends of the strol cfe; The same reference numerals havebeen used on all' of the parts 111' Figure 3 which are identical tothose; shown in Figures 1 and 2. The slide or spool valve of Figure '3designated by the numeral 25a remains in one end of the housing or theother such-as shown; u n

In the operation of this" modified construction fluid under pressure isdeliveredto the inlet port whereupon it passes around an annular groove27a and 'thence out the outlet port 21 to'etiect' operation or somefluid equipment. The annular recess 27fa is similar to the' annularrecess 27 but slightly narrower as there is no necessity of spanning thespaced outlet because the spool is never retained in aicenteredposition. How. ever, it would not be detrimental toemploy the spool 25with the wide recess 27 in the device of Figure 3. The fluid exhaustedfrom the fluid equipment (not shown) is returned through the otherspaeed ap art outlet port 22' and around the annular groove 28" forfinal discharge back to a reservoir or the lilie through the exhaustport 24. Simultaneously with the delivery of fluid to the port 21 aquantity thereof passes" inwardly through the radial passages 34 and 35to, fill the interior of the spool valve as in the device of FighresIand 2. Inasmuch as there are no springs urging movement of the spoolvalve they are therefore moved solely by differentials in'fluid"pr'essure. When the end valve 64 is opened by depressing theactuating post or stem 68 fluid within thespjool valve and within thehousing 1 0 rushes out the end opening whereupo'ri'the center valve 47closes against the valve seat with the result: that fluid in thenon-opened end of the valve ushes the spool 25 to the other end of thehousing. This causes a reversal of the direction of flow of fluidthrough the control valve and thus the fluid under pressure delivered tothe equipment to be operated is reversed. If nothing more is done thespool valve will then remain in the bore 11 of the housing 10 in theopposite end thereof. When the equilibrium of the fluid within the valveis broken the spool valve moves to the other end and stays there untilthe balance of fluids is again upset by the opening of the opposite endvalve. Thus, when the end valve 63 is opened the spool valve will thenreturn to the position in which it is shown in Figure 3. It is apparentthat the control valve of Figure 3 performs many valuable functi-ons inthe operation of fluid actuated equipment. It is similar to the valve ofFigures 1 and 2, but yet the removal of the springs brings it into adifferent category as there is no intermediate stopping and the spoolvalve is either in one end position or the other end position. Thismeans that fluid under pressure is constantly being delivered to one endof the fluid operated equipment or the other at all times.

The modification shown in Figure 4 is applicable to the control valve ofeither Figures 1 and 3 and for convenience only has been shown with thevalve of Figure 3. The purpose of the device of Figure 4 is to recoverfluid sealingflmeans and suitable passagewaysfor returning tliedischarged fluid'ba'ckto a refservoir or thelikeg 4 A in thesaiiem'anner for the devices" of Figures land si ilarreferenceipumerals"have been applied retire; parts on" the nibdifiedvalve of Figure 4; The reference numeral 83 iridica tesan; elongatedhousing corresponding to the housing 10, but for addedlength theretonecessary to include thefluidrecovery means at the'ends'there'oif. Endpllugsf are shown at 84 and 85 to provide closure; mean sflat' the'opposed' ends of the housing" 83; The end plugshave elongated reduceddiameter shoulders 8631151 87 which are externally threaded at 88 and 89forthe purpose of removable engagement with ,the internally e de eds-10f. h 'h i s -1 h mb r $0and21. are providedwithin'the" end plugshoulders 86 and s7- and are comparable in size to the chambers 55'and56 inthe' end plugs of th e' devices of Figures 1 and 3. Auxiliar$i 20chambers 92 and 93 are'also formed theendfplug sin side by siderelationship with the chambers 90' and 91 respectively. Intermediatetheadjoining chambers 90 and 92, and 91i and 93 there are provided annularoffsets or shoulders 94 and 95 respectively. Valves'96'and 97 areadaptedtoengage the offsets 94and 95 and it should be' apparent thatthefoifset's'or shoulders comprise the valve seats. Springs'98 and'99are confined within the char ber s 90 and: respectively in a mannersimilarto the springs 61 and 62 within the'charnbers 55 and 56; The:

springs 98 215699 e held within the chambers 901311515 91' byrnea'ns ofretaining washers 100 and 101' which are theriiselves held in positionby a peening over of the ends of the shoulders 86 and 87 as shown at102' and 103 Valve stems 1 04" and 105 are integrally fastened to thevalves 9:6fand and extend laterally outwardly through the endplugs'formanual depressing operation inthe same" manner as the valve stems orposts of the devices of Figuresl and 3. Aperturedpartition walls 106 andlie adjacent' to, andconstitute the outer walls for the"auxiliarychainbei-s' 9 2 and 93 and permit the slidable passageoflthe'valvestemsdil t and 105 therethrough q Thee'ndplugs; 84" and 85 areprovided" with end open": ings 108. and 109 which are internallythreaded as'shown M110 and 111. v Rubber 0 rings 1'12 and 113 surrouncithevalve stems 104 a n'd 105 within the openings 103and 109. i The fluidsealing: 0 rings are maintained in abutting partially compressedcondition against the apertured par; tition walls 106 and'1107 becauseof their engagement by externally threadedapertured' bushings 114 andllffwhich threadedly enga'geitheendopenings108" and 109. The rubberorings"v are thus confined between the apertured walls and the bushingswhereby they exert radial sealing pressure against the valve stems; Uponaxial r'n'oveme nt of the stems the rubber 0 rings rotate within theirconfined quarters but at all times remain in fluid scaling relationshipwith the stems.

Radial passages 116 and 117 are provided in the control valve housing 83adjacent the ends thereof. Aligned radial passages 118 and 119 areprovided in the elongated shoulders 86 and 87 and communicate with theauxiliary chambers 92 and 93 within the end plugs. Conduits 120 and 121respectively join the radial passages 116 and 117 with the fluidreservoir (not shown) whereby fluid exhausted or bled through the endvalves 96 and 97 may be retained within the closed fluid system.

In certain applications of the control valves of this invention it isnot necessary to recover fluid exhausted from the ends thereof in orderto actuate the valves. However, in other installations it is essentialthat the device be fluid tight and in that event the auxiliary fluidrecovery means of Figure 4 is necessary. In the operation of that devicethe control valve is again actuated by a depression of either of thevalve stems 104 and 105 whereby fluid within the valve is permitted toescape past one of the valves 96 or 97 to the auxiliary chambers 92 and93. Further axial or endwise movement of the fluid is barred by thesealing rings 112 and 113. However, the fluid is permitted to escapeback to a reservoir through the aligned radial passages 116 and 118, and117 and 119 which join the auxiliary chambers 92 and 93 with theconduits 120 and 121. Obviously the valve in every, other respectoperates as the valve of Figure 3. The only diflerence is to preventleakage of fluid at the control valve at the time of operating thereof.

It is believed important to note that all of the control valves of thisinvention are fully operable regardless of the angular dispositionthereof. The valves thus need not be horizontally disposed, but may bevertically disposed or inclined at any convenient angle without in anyway interfering with proper operation thereof.

Numerous details of construction may be varied throughout a wide rangewithout departing from the principles disclosed herein, and I thereforedo not propose limiting the patent granted hereon otherwise than asnecessitated by the appended claims.

What is claimed is:

1. A control valve for fluids comprising a housing having a cylindricalbore therethrough, a cylindrically shaped valve slidably engaging saidhousing bore, said cylindrically shaped valve having an annular groovetherearound spaced substantially centrally between the ends thereof, anda spaced apart annular groove on each side of said centrally locatedannular groove, said cylindrically shaped valve having a longitudinallydisposed substantially centrally located bore extending the lengththereof, said valve having passage means joining said centrally locatedannular groove and said longitudinally extending bore, a valve disposedwithin said longitudinally extending bore, spaced apart valve seatswithin said longitudinally extending bore and disposed on each side of acentral section thereof including said passage means, said valveslidable in the central section of said bore between said valve seats,said valve having bleed means therein, whereby when said valve ispositioned on one valve seat that seat is closed except for leakage pastthe seat to the contral section of said bore through said bleed meansand simultaneously the other of said valve seats is completely open,individual bleed valves on each end of said housing and constituting aclosure for the ends of said cylindrical bore, said housing having aninlet passage adjacent a central portion thereof and adapted tocommunicate with the centrally located annular groove, and outletpassages spaced from the inlet passage.

2. A device as set forth in claim 1 in which similar spring means arepositioned within said housing between the individual bleed valves andthe ends of said cylindrically shaped valve whereby the cylindricallyshaped valve is normallv centered within said housing.

3. A device as set forth in claim 2 in which the centrally locatedannular groove has slight communication with both of said outletpassages when the cylindrically shaped valve is centered within saidhousing.

4. A device as set forth in claim 1 in which said individual bleedvalves are normally spring closed.

5. A device as set forth in claim 4 in which each of said individualbleed valves includes a transversely disposed disc, an integral stemextending longitudinally of said housing and beyond the end thereof toconstitute manual actuating means, and end plugs for said housingthrough which the integral stems are permitted sliding movement, fluidsealing means positioned around said stems and within said end plugspermitting relative sliding move ment without passage of fluid, and portmeans in said housing adjacent said individual bleed valve stems betweenthe discs and the sealing means in the end plugs.

6. A control valve for fluids having a housing, said housing having aninlet passage and an outlet passage, a spool mounted for slidingmovement within said housing, means on said spool for directing fluidfrom the inlet passage to the outlet passage, said means including thespool having a central passage and a radial passage joining the centralpassage to the outer surface of the spool, said central passagegenerally effecting a balanced pressure condition of fluids in saidcontrol valve, separate bleed means associated with each end of thehousing, said central passage defining an enlarged chamber in the centerthereof, spaced apart seats at each side of said chamber, and a valvemember in said chamber having passage means therein, said passage meansof the valve member being smaller than the central passage through thespool, whereby when either of the bleed means is opened the valve memberslides to engagement with one of said spaced apart seats to completelyopen one seat to said enlarged chamber and close the other seat exceptfor leakage through said passage means in said valve member to saidenlarged chamber and thereby to create an out of balance pressurecondition to cause the spool to quickly move to either one end or theother of the housing.

References Cited in the file of this patent UNITED STATES PATENTS870,391 Starrett Nov. 5, 1907 1,791,613 Clay Feb. 10, 1931 2,121,936Thomas June 28, 1938 2,132,811 Tomkins Oct. 11, 1938 2,237,038 MooreApr. 1, 1941 2,261,827 Brown Nov. 4, 1941

